Means for purifying lubricating oil



Dec. 31, 1929. c. STOKES I MEANS FOR PURIFYING LUBRICATING OIL Filed March 8, 1923 IN V EN TOR.

Patented Dec. 31, 1929 CHARLES LAWRENCE STOKES, OF L OS .ANGELES, CALIFORNIA MEANS FOR PURIIYING LUBBICATING OIL Application filed March s, 1923. Serial No. 623,685.

relates to improvements in dilution of lubricases of internal My invention apparatus for removing the eating oil from the crank combustion engines.

The principal object of my invention is to circulate a lubricating oil continuously by the vacuum of'an internal combustion engine.

Another object of my invention is to utilize the same vacuum which circulates the oil to draw the oil through a filtering chamber. I

A further object of my invention is to utilize the engine vacuum to feed the removed diluent in vapor form to use in the engine cylinders.

A further object of my invention is to provide cooling means for cooling the purified lubricating oil before its return to the crank case for re-use.

Other objects will become ap arent as my invention is more fully disclose In my reissue Patent No, 14,701, I have de scribed and shown a pioneer invention for circulating lubricating oil from a crank case of an internal combustion engine by the engine induction vacuum. I accomplish this without the use of any floats etc., and utilize a novel principle therein, as fully described in said patent.

I now utilize this same principle in my present invention for circulating t e oil, but in addition thereto I utilize the vacuum, while circulating the oil, to draw the oil through a suitable filter.

Owing to the high boiling point of some of our present day gasoline components, a

large part of the gasoline taken into the cylinders of an internal combustion engine is not consumed therein, under certain conditions, and the unburnt liquid gasoline runs past the piston rings and drops into the lubricating oil contained in the crank case to which the cylinders are attached.

This unburnt gasoline forms a serious menace to the operation of an internal combustion engine, inasmuch as it not only forms a solvent for the lubricating oil on the piston and cylinder walls but it also changes adversely t e viscosity of the lubricatingoil in the ene crank case whereby the ubricating oil fies its lubricating efiiciency and in consequence engine bearings are often burnt out.

The dilution of the lubricating oil in a crank case often runs as high as 15%, with the result that the diluted lubricating oil has to be removed at times and thrown away, and in addition to this the gasoline fractions which dilute away also.

Not only is the lubricating oil are thrown this a serious economic loss, but

during the period of increasing dilution the engine is expo sed to the risk ofbeing seriously damaged by having its bearings burnt out.

It is desirable to keep the dilution down to at least 1% of the lubricating oil, and if this is done, not only is the full value of the lubricating oil obtained, but great economy results both in the mileage obtained by an automobile from its gasoline and lubricating oil consumption.

In my present invention I find that I am able to continually maintain the percentage of lubricating oil dilution below one percent.

Referring to the drawings in which the same numbers indicate like parts Fig. 1 is a diagrammatic sketch showing the application of my invention to an internal combustion engine.

Fig. 2 is a vertical section of the vacuum tank with the parts shown more or less diagrammatically.

Fig. 3 is a sectional view of a part in Fig. 1, turned through an angle of 90.

1' is an internal combustion engine having an inlet manifold 2- and an exhaust pipe 3. A vacuum tank 4 is suitably fastened to the engine and is fold 2 and by Around connected by a pipe 5 to mania pipe 6 to exhaust pipe 3.

the lower part of the manifold is placed a chamber 10, the lower part of which communicates by pipes 9, 9', with the oil reservoir 8 in the lower part of the engine crank case. Pi a check valve 9 and 9' are connected through 13, the detail of which is shown in Fig. 3. The upper art of 10 is connected with the lower part 0 4 by a pipe 11.

A second pipe 12 connects the reservoir 8 with the upper part of the vacuum tank 4 and has inse placed above mitting a $111 rted therein a small hole 14, the normal oil level X for adall quantity of air during the to the carburetor of an internal combustion engine from a low level.

In my invention, however, I use only the outer chamber 4, the inner chamber 16, and a cover 17 and do away entirely with all floats and other mechanism for the intermittent action of passing oil through 4.

The engine vacuum is applied to the tank 4 from manifold 2 by a pipe 5 which enters in the manifold at a point posterior of the throttle 28. The parts 17, 16 and 4 are held together air tight by a number of screws (not shown). s

The interior of the inner chamber 16 is filled with a filtering material such as fullers earth, kieselguhr, sand, or glass wool which is held in the chamber 16 by a fine mesh screen, or filter cloth 23 at the bottom.

Inserted through the fullers earth in 16 is a pipe 6 conveying exhaust gases in a tortuous manner 1n order to heat up the filtering material 22 for removing and straining the diluent and impurities from lubricating oil.

The passage of gases through 6 is controlled by a thermostat 19, held in a casing 18, which thermostat operates a lever 21 to open or close a valve 20 according-to desired temperature in 16.

The exhaust gases after passing through thetubes in 6 are discharged through 7 to atmosphere.

The application of engine vacuum through 5 to the interior of 4 is transmitted to the interior of 16 through a small hole 25 in the side wall of the chamber 16 and thence topipe 12 for the purpose of raising diluted lubricating oil from reservoir 8. The small vent 14 whichis above the normal level of oil in the crank case admits a small quantity of air during the operation of the engine and this lightens the oil column in the pipe 12, so that the engine suction will be sufiicient to raise the oil to the tank through the pipe 12 althou h it will not be sufficient to maintain a solid column of oil of the same height in the pipes 9, 11 and tank 4, consequently the oil will be supplied to the tank through the pipe 12 and returned to the reservoir through the pipes 9 and 11.

The operation of my system for removing the diluent from lubricating oils continuously while an engine is in operation is as follows:

While the engine is at atmospheric temperature valve 20 remains open, as shown in Fig.2, and upon cranking engine 1, heated exhaust gases are diverted from 3 into pipe 6, and pass along said pipe through the interior of the chamber 16 and the mass of filtering material 22 before they are discharged to atmosphere at 7, thus imparting their heat lubricating oil from the reservoir 8, through.

the pipe 12, filter 22, tank 4 and back to the reservoir 8, through pipes 11, 9 and 9. The air admitted through the small hole 14 is liberated in the chamber 16 and is drawn out together with the gasoline vapors through the opening 25 and pipe 5 into the intake manifold.

Until circulation is established through the passage mentioned, the engine vacuum is suflicient to cause check valve 26 to close the passage of lubricating oil through 9 until the weight of a column of oil and air being lifted in 12 is less than the weight of the solid c0lumn of oil being lifted in 9, 10, and 11 and as soon as the weight of the solid colunm of oil in 9 is suificient, check valve 26 will become unseated and held on a pin 27, thereby permitting a return flow of lubricating oil from the lower part of 4 to reservoir 8.

A differential vacuum is established in the upper part of the chamber 16, between the upper surface of the filter 22 and the cover 17 in this manner:

A high vacuum being established, through apipe 5 of comparatively large area, in the interior of 4, the same is transmitted through 25 and 23 to-the interior of 16, but the vacuum existing in 15 is always greater than the.

the filtering material 22 to the passage of air therethrough is accentuated by the closing of the interstices of 22 with lubricating oil. Therefore vacuum applied through 5 to 15, not only raises the lubricating oil, from 8 through 12 to 16, but also draws the lubricating)oil through 22 and 23 into 15.

uring the operation of the engine the diluted lubricating oil is supplied continually to the chamber 16 where it is heated by the temperature of the exhaust gases passing through the pipe 6. Such a temperature is between 400 and 600 F. and this temperature, in conjunction with the vacuum applied, is suflicient to release the vapors of gasoline fractions from the lubricating oil and cause the same to pass, along with the air admitted at 14, through the small opening 25, pipe 5 and the inlet manifold 2 into the engine cylinders where they are consumed as part of the charge.

The temperature applied to the lubricating oil in 16 should be such that cracking does not occur to destroy the value of the lubrlcating oil, and the temperature is regulated by a thermostat 19which, as the temperature rlses, is so adjusted as to maintain the interior of 16 to the desired temperature by the opening or closing of valve .20. Preferably a bi-metal thermostat is arranged in 18, but any well I known type of thermostat is suitable.

The lubricating oil, after being freed from its diluent, is drawn through 22 and 23 and deposited in 15, whence it passes through pipe 11 into 10 and 10 is arranged as a chamber around the inlet manifold 2 so that the heat of the treated lubricating oil is imparted to the incoming charge of carburetted air on its way to 2 to the engine cylinders. Thus the lubricating oil is cooled down and returned through 9, 13, and'9' to the reservoir 8 whence it is distributed to the various engine parts for lubricating purposes. The lower part of 4 is arranged as a trap for any impurities which may escape the action of 22 by having the top of 11 project a certain distance above the bottom of 4 and any such impurities maythereby settle out in the bottom of 4 and be withdrawn through a plug 24.

'Thus by continuously circulating a lubricating oil through my apparatus, I am able to 'lift the lubricating oil and draw the same through a filter, responsive to engine vacuum and thus the diluent in the lubricating oil is continuously removed whereby the oil maintains its viscosity and, to a certain degree, its

color so that its lubricating eflicienc is mamtained, thereby eliminating the anger of burnt out bearings etc., giving additional lubricating oil mileage and additional gasoline mileage. At the same time the system is automat1c in its operation and when 22 becomes sufiiciently clogged withimpurities, 16 may be easily removed and a fresh charge of filtering material may be placed therein.

I claim 2-- 1. The combination with an internal combustion engine, having an exhaust pipe for heated gases, an inlet pipe for air and fuel, and a reservoir for lubricating oil, of a filter elevated above the reservoir, an inlet and an outlet conduit for said filter, said inlet conduit having an air vent in its side wall, means the exhaust pipe, and means to cool the lubricating oil in said. inlet pipe, after passage throu h the filter.

3. g filter for urifying lubricating oils in the crank case 0% an internal combustion engine including an outer casing, an inner shell having a foraminous wall, a connection for holding the casing and shell together, pipes for heating the inner shell, a vacuum pipe connected to the outer shell and a vacuum passage of less diameter than said pipe connecting the casing and shell.

4. A filter for purifying lubricating oils in the crank case of an internal combustion engine including an outer casing, an inner shell having a foraminous wall, a connection for holding the casing and shell together, pipes for heating the inner shell, a thermostat for controlling said pipes, a vacuum pipe connected to the outer shell and a vacuum passage of less diameter than said pipe connecting the casing andshell.

igned at Wilmington, in the county of Los Angeles and State of California, this 16th da of February, A. D. 1923.

CH RLES LAWRENCE STOKES.

for applying heat from the exhaust pipe to the filter, and means for continuously applying the engine suction from the inlet pipe to.

the filter durin the operation of the engine, whereby the ln ricating oil is drawn to and through the filter and said conduits.

2. An internal combustion engine having an exhaust pipe, a fuel inlet pipe and a reservoir for lubricating oil in combination with. y

a filter elevated above the reservoir, a pipe from the inlet pipe to the filter for applying the engine suction'therethrough, a conduit.

forconducting lubricatin oil from the reservoir to the filter, said con uit being provided with an air vent, meansto heat the filter from 

